features/quota : Introducing inode quota

==========================================================================
                             Inode quota
==========================================================================
= Currently, the only way to retrieve the number of files/objects in a   =
= directory or volume is to do a crawl of the entire directory/volume.   =
= This is expensive and is not scalable.                                 =
=                                                                        =
= The proposed mechanism will provide an easier alternative to determine =
= the count of files/objects in a directory or volume.                   =
=                                                                        =
= The new mechanism proposes to store count of objects/files as part of  =
= an extended attribute of a directory. Each directory's extended        =
= attribute value will indicate the number of files/objects present      =
= in a tree with the directory being considered as the root of the tree. =
=                                                                        =
= The count value can be accessed by performing a getxattr().            =
= Cluster translators like afr, dht and stripe will perform aggregation  =
= of count values from various bricks when getxattr() happens on the key =
= associated with file/object count.                                     =

A new interface is introduced:
------------------------------
        limit-objects  : limit the number of inodes at directory level
        list-objects   : list the directories where the limit is set
        remove-objects : remove the limit from the directory

==========================================================================

CLI COMMAND:
gluster volume quota <volname> limit-objects <path> <number> [<percent>]

* <number> is a hard-limit for number of objects limitation for path "<path>"
  If hard-limit is exceeded, creation of file/directory is no longer
permitted.

* <percent> is a soft-limit for number of objects creation for path "<path>"
  If soft-limit is exceeded, a warning is issued for each creation.

CLI COMMAND:
gluster volume quota <volname> remove-objects [path]

==========================================================================

CLI COMMAND:
gluster volume quota <volname> list-objects [path] ...

Sample output:
------------------
  Path                   Hard-limit Soft-limit   Used  Available
Soft-limit exceeded?
Hard-limit exceeded?
  ------------------------------------------------------------------------
--------------------------------------
  /dir                      10       80%          10       0
Yes
        Yes

==========================================================================

[root@snapshot-28 dir]# ls
a  b  file11  file12  file13  file14  file15  file16  file17
[root@snapshot-28 dir]# touch a1
touch: cannot touch `a1': Disk quota exceeded
* Nine files are created in directory "dir" and directory is included in
* the
count too. Hence the limit "10" is reached and further file creation
fails

==========================================================================

Note: We have also done some re-factoring in cli for volume name
validation. New function cli_validate_volname is created

==========================================================================

Change-Id: I1823497de4f790a2a20ebb1770293472ea33ee2b
BUG: 1190108
Signed-off-by: Sachin Pandit <spandit@redhat.com>
Signed-off-by: vmallika <vmallika@redhat.com>
Reviewed-on: http://review.gluster.org/9769
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 67 insertions, 0 deletions

diff --git a/cli/src/cli-xml-output.c b/cli/src/cli-xml-output.c
index b6ae793131a..e5afe1b427d 100644
--- a/cli/src/cli-xml-output.c
+++ b/cli/src/cli-xml-output.c
@@ -5828,3 +5828,70 @@ out:
         return 0;
 #endif /* HAVE_LIB_XML */
 }
+
+int
+cli_quota_object_xml_output (cli_local_t *local, char *path, char *sl_str,
+                             quota_limits_t *limits, quota_meta_t *used_space,
+                             int64_t avail, char *sl, char *hl)
+{
+#if (HAVE_LIB_XML)
+        int     ret             = -1;
+
+        ret = xmlTextWriterStartElement (local->writer, (xmlChar *)"limit");
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"path",
+                                              "%s", path);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"hard_limit",
+                                               "%"PRIu64, limits->hl);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"soft_limit",
+                                               "%s", sl_str);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"file_count",
+                                               "%"PRIu64,
+                                               used_space->file_count);
+
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"dir_count", "%"PRIu64,
+                                               used_space->dir_count);
+
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"available", "%"PRIu64,
+                                               avail);
+
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                              (xmlChar *)"sl_exceeded",
+                                               "%s", sl);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                               (xmlChar *)"hl_exceeded",
+                                               "%s", hl);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+
+        ret = xmlTextWriterEndElement (local->writer);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+out:
+        return ret;
+#else
+        return 0;
+#endif /* HAVE_LIB_XML */
+}